1. Field of the Invention
The present invention relates generally to memory cards, and more particularly to a memory card (e.g., a multi-media card or secure digital card) which is configured to include at least one I/O pad adjacent the chamfer of a substrate (e.g., a printed circuit board or PCB) which is itself integrated into a module of the memory card. Further in accordance with the present invention, there is provided various methods which may be employed to facilitate the efficient, cost effective simultaneous fabrication of a plurality of modules which each include a substrate having an I/O pad adjacent the chamfer thereof.
2. Description of the Related Art
As is well known in the electronics industry, memory cards are being used in increasing numbers to provide memory storage and other electronic functions for devices such as digital cameras, MP3 players, cellular phones, and personal digital assistants. In this regard, memory cards are provided in various formats, including multi-media cards and secure digital cards.
Many memory cards include a module which itself comprises a printed circuit board (PCB) having a conductive wiring pattern disposed thereon. Attached to one side or surface of the PCB and electrically connected to the conductive pattern thereof is a plurality of electronic circuit devices, such as semiconductor packages, semiconductor dies, and/or passive elements. These electronic circuit devices and a portion of the PCB are often covered or encapsulated by an encapsulant material. The PCB also includes a plurality of input/output (I/O) pads disposed on the side or surface thereof opposite that having the electronic circuit devices thereon. These I/O pads are not covered by the encapsulant material, and thus are exposed in the completed module which comprises the PCB, the electronic circuit devices and the encapsulant material. Attached to the module is a skin or case of the memory card, such case generally defining the outer appearance of the memory card. The module is coupled to the case such that the I/O pads disposed on the PCB are not covered by the case, and thus remain exposed in the fully assembled memory card. These I/O pads of the memory card provide an external interface for an insertion point or socket. The completed memory card has a generally rectangular configuration, with most memory cards including a chamfer formed at one edge thereof which is adjacent to the I/O pads. In this regard, the I/O pads of the memory card usually extend along one of the lateral sides or edges of the card to but not along the chamfer thereof. In an effort to simplify the process steps needed to fabricate the memory card, there has been developed various memory cards wherein the case is eliminated by applying the encapsulant material the electronic devices and to the PCB such that the enapsulant material hardens into a cover or body of the memory card which is sized and configured to meet or achieve a desired “form factor” for the memory card.
The arrangement and positioning of I/O pads in the memory card module is typically dependent on the circuit construction corresponding to the electronic circuit devices included in the module and the resultant wiring patterns. As indicated above, the I/O pads of the memory card typically do not extend along the chamfer thereof. In this regard, currently known manufacturing methodologies for the mass production of memory cards are not well suited for the cost effective, simultaneous manufacture of a plurality of circuit boards which each include at least one extra I/O pad positioned along and adjacent to the memory card chamfer. The inclusion of one or more additional I/O pads along the memory card chamfer is highly desirable due to the resultant improvement in the data transfer capacity of the memory card which is an emerging requirement in many applications. For example, in the case of MMC's (multi-media cards), the construction of such cards is such that an ESC pad (which is one of the I/O pads) is positioned adjacent to the chamfer of the card and used to provide increased data transmission speed. In accordance with the currently known methods used to facilitate the construction of memory cards including one or more additional I/O pads adjacent the chamfer, the chamfer of the module must typically be directly formed on the encapsulant body of the module by a mold, with the PCB of such module being singulated from a single row of PCB's in a substrate, rather than such PCB's being arranged in a matrix within the substrate. The result is increased time and complexity in the manufacturing process, and thus in the overall cost for the memory card module.
The present invention addresses and overcomes the above-described shortcomings of the prior art by providing various methods which may be employed to facilitate the efficient, cost effective simultaneous fabrication of a plurality of modules which each include a substrate (e.g., a printed circuit board or PCB) having at least one I/O pad adjacent a chamfer formed therein. These modules are each integrated into a memory card which is configured to include at least one additional I/O pad adjacent the chamfer defined thereby. These and other attributes of the present invention will be described in more detail below.